JP6742587B2 - Combination with screw holding type driver bit and screw - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention improves the structure of the tip portion of the driver bit to enable easy and quick fitting and mounting in the bit fitting groove provided in the screw head of the screw applied to this driver bit. In combination with a screw holding type driver bit and screw that can surely exhibit the screw holding function at the tip of the driver bit and effectively prevent the cam out phenomenon during screw tightening work, and significantly improve the work efficiency. is there.

The present applicant previously provided a plurality of flat blade portions having substantially vertical edge portions at the tip portion, and configured the tip center portion of these flat blade portions as a conical projection portion, and any one of the above. While cutting the flat blade portion in the bit axis direction with respect to the flat blade portion, a long groove is engraved as a guide passage of a required length on the continuous shaft portion on substantially the extension of the cut portion of the flat blade portion, From a configuration in which an elastic piece having a screw holding function is inserted and arranged in the long groove by elastically abutting against the bit fitting groove of the screw head and interacting with the flat blade part fitted in the bit fitting groove. Developed a screw holding type driver bit and obtained a patent (see Patent Document 1).

That is, in the screw holding type driver bit described in Patent Document 1, the flat blade portion of the driver bit is cut in the axial direction of the driver bit to form a long groove of a required length, and a screw is inserted in the long groove. Since the elastic piece having a holding function is inserted and arranged, the structure is relatively simple, so manufacturing and maintenance are easy, and when holding the screw, the flat blade part at the tip of the driver bit is fitted. As a result, since only the pressure contact elastic force of the elastic piece is used, it is possible to exert a reliable and stable screw holding function without requiring the combined use of a suction force by a magnet or air as in the conventional case. Is.

Further, in Patent Document 1, as an example of the screw holding type driver bit having the above-described configuration and a screw adapted thereto, a deformed hexagonal hole (hexalobular or the like) is provided as a bit fitting groove of a screw head. There is also proposed a structure including a screw and a deformed hexagonal corner portion so as to match with a bit fitting groove of the screw. Therefore, in this kind of screw holding type driver bit, a corner is cut in the bit axial direction with respect to one of the corners of the deformed hexagon, and the cut part of the corner is cut off. A deformed hexagonal shape in which a long groove having a required length is engraved in a continuous shaft portion in extension and elastically abutted against the bit fitting groove of the screw head in the long groove and fitted into the bit fitting groove. There is also proposed a structure in which an elastic piece having a screw retaining function is inserted and arranged by interaction with the corners of the.

Further, conventionally, like a screw provided with a deformed hexagonal hole (hexalobular or the like) described in Patent Document 1, three or more recessed recesses protruding toward the outer peripheral side at equal angular intervals are provided in the screw head. Screw and a screw tightening tool that has a torque transmission part consisting of a fitting protrusion that fits into the recess of this screw, a screw tightening structure has been proposed in which a cam out that the screw tightening tool slips out of the recess does not easily occur. (See Patent Document 2).

However, in the screw tightening structure described in Patent Document 2, the outer peripheral end of the torque transmitting portion of the fitting protrusion of the screw tightening tool is brought into contact with the side wall surface of the torque transmitting portion of the recess of the screw. , The tightening force is transmitted to the screw via the contact point Q which is the contact portion, and the cross-sectional shape or end face shape of the recess perpendicular to the center line O1 of the recess including the contact point Q has When the direction of the surface normal force F perpendicular to the side wall of the recess is the angle of inclination from the tangential direction of the force application point Q with the center line O1 as the center, the driving angle θ is outward from the cutting line direction. As a positive value, θ≦0°, and particularly in the case of θ<0°, the fitting convex portion bites into the recess, and the camout is suppressed more appropriately, and the above-mentioned effect becomes remarkable. It is supposed to be.

Furthermore, conventionally, in a screw head, a screw tightening system by a screw having an insertion port of a hexalobular and a tool for use in the screw, particularly, a sufficient fitting between the tool and the hexalobular screw. A system that realizes a fit has been proposed (see Patent Document 3).

That is, the screw tightening system described in Patent Document 3 includes (1) an upper surface of a head of a hexalobular insertion port on the upper surface of the head, and a flat surface of the hexalobular surface of the screw head extending below or parallel to the screw axis. A screw having a peripheral wall, a corresponding tool, and (2) a transition surface extending downward and inward with respect to the lower edge of the upper peripheral wall, and a taper extending downward from the lower edge of the inclined transition surface. Is a system for tightening a screw, which comprises a central recess of (3), the head of the screw having a size to be engaged with a tool having a central portion serving as an upper engaging surface and a lower engaging surface. (4) The upper engagement surface is the angle at which the tool is engaged with the screw shaft, is slightly sharper than the upper peripheral wall of the screw, and is tapered downward (5 ) The central part, which is the lower engagement surface, is aligned with the central recess of the screw so that a "shock fit" is achieved with the surface of the tapered central recess and there is no engagement with the sloping transition surface. At the same angle, the taper is tapered downward.

Therefore, according to the screw tightening system described in Patent Document 3, the screw does not fall off by forming a contact by compression between the central portion of the tool and the central concave portion which is the tapered portion of the screw head. It is mentioned that it is possible to stay in the tool.

Japanese Patent No. 4280457 Japanese Patent No. 5238076 Japanese Patent No. 5133979

According to the combination of the screw holding type driver bit and the screw described in Patent Document 1 of the applicant's earlier application, the polygonal shape other than the bit fitting portion formed of the cross groove, which has been difficult in the past, is formed. Although it is possible to apply to a screw having a bit fitting portion, when a screw having a polygonal bit fitting portion is used, a configuration of an elastic piece having a screw holding function provided at the shaft tip portion of the driver bit is used. In the disposition, when the tip portion of the elastic piece is brought into contact with the bit fitting portion provided on the screw head, the tip thereof is pressed against the periphery of the opening edge portion of the bit fitting groove based on the displacement of the elastic piece, There is a problem that the surface of the screw head is unexpectedly damaged, and in order to prevent this, when the displacement amount of the elastic piece is reduced, the elasticity of the elastic piece for generating the screw holding function is reduced. There are difficulties.

In addition, in the screw tightening structure described in Patent Document 2, the screw tightening tool and the basic structure of the screw have the conventional rail structure, and the outer peripheral side end of the torque transmitting portion of the fitting protrusion of the screw tightening tool is used. When the tightening torque is transmitted to the screw via the force applying point Q which is the contact portion when the portion abuts the side wall surface of the torque transmitting portion of the recess for the screw, the recess at the force applying point Q is transmitted. In the cross-sectional shape or end face shape of the recess that is perpendicular to the line O1 of FIG. 1, the drive angle θ of the surface normal force F perpendicular to the side wall of the recess at the force application point is set to a predetermined angle. Producing the screw tightening tool and the screw so as to be compatible requires precise and complicated design and production, and even when the foreign matter or the like intrudes into the abutting portion at the time of use, the required purpose is achieved. It is difficult to achieve this, and proper screw tightening work cannot be performed.

Further, in the screw tightening system described in Patent Document 3, a screw having a hexalobular upper engagement surface at the head of the screw and a tool corresponding to the screw are provided, and the screw is formed from the upper engagement surface. A tapered central recess is formed via a downwardly sloping transition surface, the tool is provided with a corresponding central part, and a "tight fit" is realized with the surface of the central recess of the screw. When forming the taper central recess of the screw and the taper central portion of the tool, similar to the above, precise and complicated design and manufacture are required, and also in use thereof. If foreign matter or the like enters the fitting portion, it becomes difficult to achieve a desired purpose, and proper screw tightening work cannot be performed.

Therefore, the present inventor has conducted extensive studies and studies in order to solve the above-mentioned conventional screw and a tool applied to the screw, that is, a driver bit. a screw having a bit fitting portion formed six torque transmitting groove to extend respectively spaced at each such angular intervals, six fitting projection adapted to the bit fitting portion of the screw In combination with a driver bit having a shaft tip portion formed on the outer peripheral surface of a torque transmitting portion consisting of an outer peripheral surface along all opening edges of the six torque transmitting grooves. A guide opening that expands to the required width and is inclined downward toward the center of the screw shaft, and at the tip of the shaft of the driver bit to fit the bit fitting portion of the screw. One of the formed fitting protrusions of the torque transmission portion is partially cut from the tip thereof along the bit axis direction to form a cutout portion. Next, with the tip end of the shaft tip of the driver bit exposed, a protective sleeve is attached so as to surround the outer periphery of the shaft tip having the notch, and the shaft tip surrounded by the protection sleeve is attached. An elastic pin that can be elastically displaced in the radial direction and the circumferential direction of the shaft is inserted into the cutout portion of the shaft, and the tip end portion of the elastic pin exposed from the protection sleeve is positioned slightly rearward from the tip end of the cutout portion. The shaft is arranged so as to be displaced slightly outward in the radial direction from the outer peripheral surface of the shaft. Then, when the fitting convex portion at the shaft tip portion of the driver bit is brought into contact with the bit fitting portion of the screw, the tip portion of the elastic pin provided at a part of the fitting convex portion is the bit. The guide opening formed in the fitting portion abuts while being elastically displaced in the radial direction and the circumferential direction of the shaft , respectively , and sequentially in the torque transmission groove of the bit fitting portion with respect to the outer side and the circumferential direction of the shaft. We have succeeded in developing a combination with a screw holding type driver bit and a screw that can be screwed into each other to generate a screw holding function.

That is, the screw holding type driver bit having the above-mentioned configuration and the combination with the screw allow relatively easy design and configuration to be manufactured easily and at low cost, and further, such a special bit. When connecting the driver bit to the screw with the fitting groove, it is possible to achieve smoothly and efficiently without causing damage to the screw head, and to reliably and firmly exert a strong screw holding function. I found it.

In addition, in the combination of the screw holding type driver bit and the screw having the above-mentioned configuration, the elastic pin provided at the tip of the shaft of the driver bit uses a piano wire rod having a circular cross section having a high tensile strength and the tip edge thereof. By using a chamfered piece, the tip end of the elastic pin contacts the guide opening formed in the bit fitting portion of the screw while elastically displacing in the radial and circumferential directions of the shaft. In addition, it can be inserted into the torque transmission groove of the bit fitting part so as to make pressure contact with the shaft in the radial direction and in the circumferential direction. The connection between the driver bit and the screw can be achieved quickly.

Further, as a combination of the screw holding type driver bit having the above-mentioned configuration and the screw, for example, a screw bit having a hexalobular shape in the torque transmission groove of a bit fitting portion which is currently commercially available in a large amount and a driver bit corresponding to this screw are provided. If applied, all the above-mentioned actions and effects can be effectively exhibited.

Therefore, an object of the present invention is to provide a bit fitting portion in which six torque transmission grooves are formed on the top surface of a screw head so as to extend at equal angular intervals with respect to a circular outer peripheral portion. Provided on the screw head in combination with a screw and a driver bit having a shaft tip portion formed on the outer peripheral surface with a torque transmitting portion consisting of six fitting protrusions that fit the bit fitting portion of the screw. To provide a combination with a screw holding type driver bit and a screw that can be easily and smoothly fitted and mounted in a bit fitting groove and can surely exert a screw holding function at a tip portion of a driver bit. It is in.

In order to achieve the above-mentioned object, a combination of a screw holding type driver bit and a screw according to claim 1 of the present invention has a top surface of a screw head (30a) at equal angular intervals with respect to a circular outer peripheral portion. and apart from screws bit fitting portion formed with six torque transmission groove (34) so as to extend respectively (32) is provided (30), adapted to the bit fitting portion of the screw (32) A combination with a driver bit (10) having a shaft tip (16) having an outer peripheral surface formed with a torque transmission portion (14) composed of six fitting protrusions (12) ,
The bit fitting portion (32) of the screw (30) has a required width extending outward along the full opening edge portion (34a) of the six torque transmission grooves (34) and the center of the screw shaft. guide opening portion inclined downwardly directed in part to form a (36), the shaft tip portion of a driver bit (10) to (16), to match the bit fitting portion of the screw (32) Any one of the fitting convex portions (12) of the torque transmitting portion (14) formed in the above is partially cut from the tip thereof along the bit axial direction to form the cutout portion (18) , and the driver bit ( Protective sleeve (20) so as to surround the outer periphery of the shaft tip portion (16) having the cutout portion (18) in a state where the tip end portion (16a ) of the shaft tip portion (16) of ( 10) is exposed. With the configuration attached,
An elastic pin (22) that can be elastically displaced in the radial direction and the circumferential direction of the shaft is inserted into the notch (18) of the shaft tip (16) surrounded by the protective sleeve (20), and the protective sleeve The tip end portion (22a) of the elastic pin (22) exposed from (20) is located slightly rearward of the tip end of the cutout portion (18) and is displaced slightly outward in the radial direction from the outer peripheral surface of the shaft. Place and
When the fitting protrusion (12) on the shaft tip (16) of the driver bit (10) abuts on the bit fitting portion (32) of the screw (30) , the fitting protrusion (12). A tip portion (22a ) of the elastic pin (22) provided on a part of the elastic elastic member is elastically displaced in the guide opening (36) formed in the bit fitting portion (32) in the radial direction and the circumferential direction of the shaft , respectively. While abutting with each other , they are sequentially fitted into the torque transmission groove (34) of the bit fitting portion (32) so as to come into pressure contact with the radial direction outside and the circumferential direction of the shaft, respectively, to generate a screw holding function. It is characterized in that it is configured as follows.

According to the combination of the screw holding type driver bit and the screw according to the first aspect of the present invention, it is possible to easily manufacture at low cost with a relatively simple design and construction, and to use this special type. When connecting a driver bit to a screw with a special bit fitting groove, it is possible to achieve smoothly and efficiently without causing damage to the screw head, and to ensure that the screw holding function is fully exerted. Therefore, the work efficiency of the screw tightening work can be significantly improved.

That is, in the combination of a screw holding type driver bit and a screw according to claim 1 of the present invention, an elastic pin provided on the shaft distal end portion of the driver bit, for example, using a circular cross section of a piano wire having a high degree of tensile strength In addition, the tip edge is appropriately chamfered so that it can be inserted into the notch of the shaft tip surrounded by the protective sleeve so that it can be elastically displaced in the radial and circumferential directions of the shaft. In addition, it is possible to securely and effectively generate a screw holding function by fitting in the torque transmission groove of the bit fitting portion so as to make pressure contact with the shaft in the radial direction and in the circumferential direction. There is .

Therefore, as a combination with the screw holding type driver bit and the screw of the present invention having the above-mentioned structure , for example, a screw having a hexagonal-shaped torque transmission groove of a bit fitting portion, which is commercially available at present, corresponds to this screw. By applying it to a driver bit, it is possible to effectively exhibit all the above-mentioned actions and effects.

It is a schematic perspective view which shows the Example of the combination with the screw holding type|mold driver bit and screw which concern on this invention. It is a principal part top view of the front-end|tip part of the screw holding type|mold driver bit which concerns on this invention shown in FIG. FIG. 3 is a sectional view of the main part of the driver bit shown in FIG. It is a top view of the screw head of the screw corresponding to the screw holding type driver bit which concerns on this invention shown in FIG. It is the BB sectional view taken on the line of the screw shown in FIG. FIG. 3 is a cross-sectional view of relevant parts showing a state in which coupling between the screw holding type driver bit according to the present invention shown in FIG. 1 and a screw is started. FIG. 7 is a cross-sectional view of essential parts showing a coupled state of a screw holding type driver bit according to the present invention shown in FIG. 6 and a screw.

Next, embodiments of a combination of a screw holding type driver bit and a screw according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a schematic perspective view showing an exemplary embodiment of a combination of a screw holding type driver bit and a screw according to the present invention. That is, FIG. 1 is a schematic perspective view showing a screw holding type driver bit 10 according to the present invention and a main part of a screw 30 applied to the driver bit 10, and FIGS. 2 and 3 are shown in FIG. FIGS. 4 and 5 are a plan view and a cross-sectional view of a main part showing a detailed configuration of a screw holding type driver bit 10, and FIGS. 4 and 5 are a plan view of a screw head showing a detailed configuration of the screw 30 shown in FIG. FIG.

Therefore, in FIG. 1 to FIG. 3, a screw holding type driver bit 10 according to the present invention has a torque transmitting portion 14 composed of a plurality of fitting convex portions 12 that fit into a bit fitting portion 32 of a screw 30 described later. It has a shaft tip portion 16 formed in the above. In the illustrated example, a screw holding type driver bit 10 having a hexagonal torque transmitting portion 14 having six fitting protrusions 12 is shown.

At this shaft tip portion 16, one fitting convex portion 12 of the torque transmission portion 14 formed so as to fit the bit fitting portion 32 of the screw 30 is partially provided along the bit axial direction from the tip thereof. A cutout 18 is formed by cutting. The tip end portion 16a of the shaft tip portion 16 is appropriately exposed, and a protective sleeve 20 is attached so as to surround the outer periphery of the shaft tip portion 16 in which the cutout portion 18 is formed. An elastic pin 22 is inserted and arranged in the notch 18 of the shaft tip portion 16 surrounded by 20 so as to be elastically displaced in the radial direction and the circumferential direction of the shaft. Therefore, in this case, as the elastic pin 22, it is possible to use, for example, a piano wire having a circular cross section having a high tensile strength and a chamfered end edge thereof.

The end 22a of the elastic pin 22 which is exposed from the protective sleeve 20, causes slightly positioned behind the front end of the notch portion 18, positioned to slightly displaced radially outward from the outer circumferential surface of the shaft.

1 and 4 and 5, the screw 30 according to the present invention has an equal angle to the circular outer peripheral portion on the top surface of the screw head 30a. The bit fitting portion 32 is provided with a plurality of torque transmission grooves 34 formed so as to be spaced apart from each other and extend outward in the radial direction. In the illustrated example, the screw 30 has a hexagonal bit fitting portion 32 having six torque transmission grooves 34.

Then, the bit fitting portion 32 of the screw 30 is expanded outward with a required width along the entire opening edge portions 34a of the plurality of torque transmission grooves 34, and is directed downward toward the center portion of the screw shaft. It has a structure in which a slanting guide opening 36 is formed.

In the screw holding type driver bit 10 and the screw 30 having the above-mentioned configurations, the central portion of the tip of the shaft tip portion 16 of the screw holding type driver bit 10 for mutual coupling and the bit fitting portion 32 of the screw 30. By configuring the configuration with the central bottom portion as shown in FIGS. 1 to 5, respectively, the coupling operation in the screw tightening work can be performed easily, properly and quickly.

That is, in the screw holding type driver bit 10, the central portion of the shaft tip portion 16 is located from the peripheral edge of the cylindrical portion corresponding to the inscribed circle of each fitting convex portion 12 forming the torque transmitting portion 14 of the shaft tip portion 16. projecting concave curve shape that tapers directed in and constitute a tip as the tip protrusion 24 that protrudes formed in a conical shape.

On the other hand, the screw 30 is tapered toward the center of the bit fitting portion 32 from the peripheral edge of the cylindrical portion corresponding to the inscribed circle of each torque transmission groove 34 of the bit fitting portion 32. It is formed in a convexly curved concave portion, and the central portion thereof is formed as a central bottom surface portion 38 formed in a conical concave portion.

Therefore, the screw holding type driver bit 10 having the above-described configuration uses the screw 30 having the above-described configuration when performing screw tightening work, as shown in FIG. The tip end of the shaft tip portion 16 can be opposed to the bit fitting portion 32 of the screw 30. That is, in this case, the fitting protrusions 12 of the torque transmission portion 14 formed on the shaft tip portion 16 of the screw holding type driver bit 10 are replaced with the torque transmission grooves 34 formed on the bit fitting portion 32 of the screw 30. And can face each other.

In this case, the tip portion 22a of the elastic pin 22 provided on the shaft tip portion 16 does not contact the surface of the screw head 30a of the screw 30 at the beginning, and the shaft tip of the screw holding type driver bit 10 does not come into contact. As shown in FIG. 6, the fitting convex portions 12 of the portion 16 are fitted into the torque transmitting grooves 34 of the bit fitting portion 32 of the screw 30 so that the tip end portion of the elastic pin 22 is formed. 22a comes into contact with the guide opening 36 provided in the bit fitting portion 32 of the screw 30.

In this manner, the tip end portion 22a of the elastic pin 22 is in contact with the guide opening portion 36 of the screw 30, and the screw holding type driver bit 10 shaft tip portion 16 is connected to the bit fitting portion of the screw 30. When the elastic pin 22 is inserted into 32, the distal end portion 22a of the elastic pin 22 moves smoothly along the inclined surface of the guide opening portion 36 while maintaining elasticity in the radial direction outward and in the circumferential direction . As shown in FIG. 5, it can be securely fitted into any of the torque transmission grooves 34 in the bit fitting portion 32 of the screw 30. That is, when the fitting protrusion 12 on the shaft tip portion 16 of the driver bit 10 comes into contact with the bit fitting portion 32 of the screw 30, the elastic pin 22 provided on a part of the fitting protrusion 12 is provided. Of the bit fitting portion 32 is abutted against the guide opening portion 36 formed in the bit fitting portion 32 while elastically displacing in the radial direction and the circumferential direction of the shaft, respectively. In the radial direction of the shaft and in the circumferential direction of the shaft so as to be pressed into contact with each other so as to be smooth and generate a reliable screw holding function.

Therefore, according to the combination of the screw holding type driver bit and the screw according to the present invention having the above-mentioned configuration, it is possible to easily manufacture at low cost with a relatively simple design and structure. When connecting a driver bit to a screw with a special bit fitting groove, it is possible to achieve smoothly and efficiently without damaging the screw head, and to ensure a firm and strong screw holding function. Therefore, the work efficiency in this type of screw tightening work can be significantly improved.

Although the preferred embodiment of the present invention has been described above, the screw holding type screwdriver bit according to the present invention is not limited to the above-described embodiment, and for example, a torque including five or three fitting convex portions is used. It can also be configured as a screw holding type driver bit having the transmission portion 14. Further, the screw applied to the screw holding type driver bit is not limited to the above-described embodiment, but may be a screw having a bit fitting portion composed of, for example, five or three torque transmission grooves. .. In addition, it is needless to say that various design changes and the like can be made in the shape and the configuration of the screw holding type driver bit and various parts as the screw without departing from the spirit of the present invention.

10 Driver Bit 12 Fitting Convex Part 14 Torque Transmitting Part 16 Shaft Tip 16a Cutting Edge Part 18 Notch 20 Protective Sleeve 22 Elastic Pin 22a Tip Part 24 Tip Projection 30 Screw 30a Screw Head 32 Bit Fitting 34 Torque Transmission Groove 34a Opening edge 36 Guide opening 38 Central bottom surface

Claims (1)

On the top surface of the screw head (30a) , a bit fitting portion (32) having six torque transmission grooves (34) formed so as to extend at regular angular intervals with respect to the circular outer peripheral portion is formed. A shaft tip (16 ) having a torque transmission part (14) formed on the outer peripheral surface, the torque transmission part (14) including the provided screw (30) and six fitting protrusions (12) adapted to the bit fitting part (32) of the screw. ) With a driver bit (10)
The bit fitting portion (32) of the screw (30) has a required width extending outward along the full opening edge portion (34a) of the six torque transmission grooves (34) and the center of the screw shaft. guide opening portion inclined downwardly directed in part to form a (36), the shaft tip portion of a driver bit (10) to (16), to match the bit fitting portion of the screw (32) Any one of the fitting convex portions (12) of the torque transmitting portion (14) formed in the above is partially cut from the tip thereof along the bit axial direction to form the cutout portion (18) , and the driver bit ( Protective sleeve (20) so as to surround the outer periphery of the shaft tip portion (16) having the cutout portion (18) in a state where the tip end portion (16a ) of the shaft tip portion (16) of ( 10) is exposed. With the configuration attached,
An elastic pin (22) that can be elastically displaced in the radial direction and the circumferential direction of the shaft is inserted into the notch (18) of the shaft tip (16) surrounded by the protective sleeve (20), and the protective sleeve The tip end portion (22a) of the elastic pin (22) exposed from (20) is located slightly rearward of the tip end of the cutout portion (18) and is displaced slightly outward in the radial direction from the outer peripheral surface of the shaft. Place and
When the fitting protrusion (12) on the shaft tip (16) of the driver bit (10) abuts on the bit fitting portion (32) of the screw (30) , the fitting protrusion (12). A tip portion (22a ) of the elastic pin (22) provided on a part of the elastic elastic member is elastically displaced in the guide opening (36) formed in the bit fitting portion (32) in the radial direction and the circumferential direction of the shaft , respectively. While abutting with each other , they are sequentially fitted into the torque transmission groove (34) of the bit fitting portion (32) so as to come into pressure contact with the radial direction outside and the circumferential direction of the shaft, respectively, to generate a screw holding function. A combination with a screw holding type driver bit and a screw characterized by being configured as described above.

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